Problem: Kevin starts counting at 29, and he counts by fives. If 29 is the 1st number that Kevin counts. what is the 15th number that he counts?
Solution: What is the first number that he counts? $29$ What is the second number that he counts? $\begin{align*}&29 + 5 \\ &= 34\end{align*}$ What is the third number that he counts? $\begin{align*}&29 + 5 + 5 \\ &= 29 + (2 \times 5) \\ &= 39\end{align*}$ What is the 15th number that he counts? $\begin{align*}&29 + (14\times5) \\ &= 29 + 70 \\ &= 99\end{align*}$